New studies show that our alien neighbor Mars is treating its own moon as a hostile object and is slowly but surely crushing it. According to a report published in early November by the magazine The Planetary Science Journalthe long horizontal grooves on the surface of the moon Phobos are actually deep cracks that gradually deepen and widen over time.
New scientific models suggest that the grooves on Phobos may have formed as a result of tidal forces – the mutual gravitational attractions of the planet and the moon. At the same time, scientists originally believed that they were formed as a result of the impact of another space body, which created the Stickney impact crater with a diameter of almost ten kilometers.
Grooves on Phobos
Research has shown that the larger of Mars’ two moons – Phobos – is literally being torn apart by the planet’s strong gravitational forces. Peculiar features stretching across its surface, originally thought to be scars from a long-ago collision with an asteroid, are actually dust-filled canyons that are growing larger as the moon is further stretched by gravitational forces.
These findings may indicate the future fate of Phobos. The moon revolves around Mars in a spiral orbit, within which is approaching it at a rate of 1.8 meters per hundred years. If it continues at this rate, within fifty million years it will either collide with Mars, or it will spontaneously disintegrate.
According to scientists, Phobos is now balancing on the so-called Roche gap, which is the theoretical limit of the distance beyond which one body, held together only by its own gravity, is torn apart by the tidal forces of the other body. However, the intrepid moon is approaching Mars, and since it’s basically a giant ball of compacted soil, it’s possible that it’s “tearing at the seams” as it moves.
The moon that approaches
That is why they are found on its surface long, shallow, parallel grooves, which were a great mystery to scientists. Approaching the planet causes global tidal stress, which is the driving force behind the formation of cracks.
This hypothesis is not entirely new, but was considered unlikely in the past due to how dusty and loose the surface of Phobos appeared to be. But new research has found, based on computer simulations, that there could be a stronger layer beneath the surface that holds the moon together — and that is slowly cracking as a result.
Scientists predict that the moment Phobos finally crosses the threshold where Mars’ gravitational pull is stronger than the internal gravity that holds the moon together, Phobos shatters. Its pieces will then continue to orbit the planet in a belt similar to Saturn’s rings.